Journal
JOURNAL OF ORTHOPAEDIC RESEARCH
Volume 28, Issue 1, Pages 131-138Publisher
WILEY
DOI: 10.1002/jor.20956
Keywords
mesenchymal stem cell; thymosin; actin; adipocyte adhesion molecule
Categories
Funding
- Taipei Medical University [TMU97-AEI-B22]
- Taipei Veterans General Hospital [VGH97E1-007]
- National Science Council [NSC95-2745-B-010-003-MY3, NSC97-2627-B-010-010, NSC97-3111-B-010-003, NSC95-2314-B-010-099-MY2]
- Ministry of Education, Aim for the Top University Plan
Ask authors/readers for more resources
Change of actin filament organization at the early stage of cell differentiation directs cell fate commitment of mesenchymal stem cells (MSCs). Thymosin beta-4 (T beta(4)), a major G-actin sequestering peptide, is known to regulate the cytoskeleton. The study investigated the ways in which T beta(4) regulates cell fate determination in MSCs upon differentiation induction. It was found that T beta(4) decreased F-actin formation, reduced the F-actin/G-actin ratio, and inhibited osteogenic differentiation; such actin reorganization was not associated with the change of Runt-related transcription factor 2 gene expression during early osteogenic induction. Besides, T beta(4) reciprocally facilitated adipogenic differentiation. T beta(4) treatment was found to up-regulate gene as well as promote surface expression of adipocyte adhesion molecule during early adipogenic differentiation, which accompanied acceleration of adipocyte phenotypic maturation but was not associated with differential expression of peroxisome proliferator-activated receptor gamma during the first week of adipogenic induction. In summary, T beta(4) initiated cell fate determination of MSCs through biophysical effects exerted by cytoskeleton reorganization and altered cell-cell adhesion rather than direct regulation of lineage-determining transcriptional factors. Such findings suggest that T beta(4), a ubiquitous peptide, may be involved in osteoporosis when its intracellular concentration is elevated. Further investigation of targeting T beta(4) for future osteoporosis treatment is warranted. (C) 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:131-138, 2010
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available